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Willett, Christopher G.

https://orcid.org/0000-0002-4573-4302

Mayo Clinic

Duke University

Citations 23

Gastric Cancer, Version 2.2025, NCCN Clinical Practice Guidelines In Oncology
Ajani, Jaffer A. , D’Amico, Thomas A., Bentrem, David J., Corvera, Carlos U. , Das, Prajnan , Enzinger, Peter C. , Enzler, Thomas , Gerdes, Hans, Grierson, Patrick , Hofstetter, Wayne L. , Ilson, David H. , Jalal, Shadia I. , Kleinberg, Lawrence , Lacy, Jill , Lee, Byrne , Licciardi, Frank, Ly, Quan P. , Matsukuma, Karen , McNamara, Michael, Mukherjee, Sarbajit , Mulcahy, Mary F. , Reddi, Deepti , Reznik, Scott I. , Roses, Robert E. , Strong, Vivian E. , Su, Stacey, Uboha, Nataliya V. , Willett, Christopher G. , Yoon, Harry H. , McMillian, Nicole R., Stein, MaryElizabeth , Gupta, Garima , Ajani, Jaffer A , Bentrem, David J. , Gibson, Michael K. , Gupta, Garima , Kim, Sunnie S. Y. , Klempner, Samuel J. , Lloyd, Shane , Merkow, Ryan P. , Perry, Kyle A. , Pimiento, José M. , Reddi, Deepti , Wainberg, Zev A. , Woo, Yanghee

Journal of the National Comprehensive Cancer Network | May 8, 2025 | Volume: 23 | Issue: 5 | Pages: 169-191

10.6004/jnccn.2025.0022 Get It

Gastric cancer is the fifth leading cause of cancer-related deaths worldwide. Over 95% of gastric cancers are adenocarcinomas, which are typically classified based on anatomic location and histologic type. Gastric cancer generally carries a poor prognosis because it is often diagnosed at an advanced stage. Systemic therapy can provide palliation, improve survival, and enhance the quality of life in patients with locally advanced or metastatic disease. The implementation of biomarker testing has had a significant impact on clinical practice and patient care. Targeted therapies have demonstrated encouraging results in clinical trials for the treatment of patients with locally advanced or metastatic disease. This selection from the NCCN Clinical Practice Guidelines in Oncology for Gastric Cancer highlights recommendations for biomarker testing and discusses updates for the treatment of advanced disease, including peritoneal carcinoma as only disease and unresectable locally advanced, recurrent, or metastatic disease.
NCCN Guidelines® Insights: Rectal Cancer, Version 3.2024
Benson, Al B. , Adam, Mohamed A. , Chang, George J. , Chen, Yi-Jen, Cooper, Harry S. , Deming, Dustin A. , Garrido‐Laguna, Ignacio , Grem, Jean L. , Haste, Paul, Hecht, J. Randolph, Hoffe, Sarah E. , Hunt, Steven R., Johung, Kimberly L. , Joseph, Nora, Kirilcuk, Natalie, Krishnamurthi, Smitha , Malla, Midhun , Maratt, Jennifer K. , Messersmith, Wells A. , Meyerhardt, Jeffrey A. , Mulcahy, Mary F. , Nurkin, Steven, Parikh, Aparna, Patel, Hitendra , Shibata, David , Shogan, Benjamin D. , Skibber, John M., Sofocleous, Constantinos T. , Tavakkoli, Anna , Willett, Christopher G. , Wu, Christina, Jones, Frankie, Gurski, Lisa A., Meyerhardt, Jeffrey A , Venook, Alan P. , Chen, Yi‐Jen , Ciombor, Kristen K. , Cohen, Stacey A. , Hussan, Hisham , Miller, Eric D. , Patel, Hitendra, Pedersen, Katrina S. , Saltz, Leonard B. , Schneider, Charles John

Journal of the National Comprehensive Cancer Network | August 16, 2024 | Volume: 22 | Issue: 6 | Pages: 366-375

10.6004/jnccn.2024.0041 Get It

The determination of an optimal treatment plan for an individual patient with rectal cancer is a complex process. In addition to decisions relating to the intent of rectal cancer surgery (ie, curative or palliative), consideration must also be given to the likely functional results of treatment, including the probability of maintaining or restoring normal bowel function/anal continence and preserving genitourinary functions. Particularly for patients with distal rectal cancer, finding a balance between curative-intent therapy while having minimal impact on quality of life can be challenging. Furthermore, the risk of pelvic recurrence is higher in patients with rectal cancer compared with those with colon cancer, and locally recurrent rectal cancer is associated with a poor prognosis. Careful patient selection and the use of sequenced multimodality therapy following a multidisciplinary approach is recommended. These NCCN Guidelines Insights detail recent updates to the NCCN Guidelines for Rectal Cancer, including the addition of endoscopic submucosal dissection as an option for early-stage rectal cancer, updates to the total neoadjuvant therapy approach based on the results of recent clinical trials, and the addition of a “watch-and-wait” nonoperative management approach for clinical complete responders to neoadjuvant therapy.
Colon Cancer, Version 3.2024, NCCN Clinical Practice Guidelines in Oncology
Benson, Al B. , Adam, Mohamed A. , Chang, George J. , Chen, Yi-Jen, Cooper, Harry S. , Deming, Dustin A. , Garrido‐Laguna, Ignacio , Grem, Jean L. , Haste, Paul, Hecht, J. Randolph, Hoffe, Sarah E. , Hunt, Steven R., Johung, Kimberly L. , Joseph, Nora, Kirilcuk, Natalie, Krishnamurthi, Smitha , Malla, Midhun , Maratt, Jennifer K. , Messersmith, Wells A. , Meyerhardt, Jeffrey A. , Mulcahy, Mary F. , Nurkin, Steven, Overman, Michael J. , Parikh, Aparna, Patel, Hitendra , Shibata, David , Shogan, Benjamin D. , Skibber, John M., Sofocleous, Constantinos T. , Tavakkoli, Anna , Willett, Christopher G. , Wu, Christina, Gurski, Lisa A., Snedeker, Jenna, Jones, Frankie, Meyerhardt, Jeffrey A , Venook, Alan P. , Chen, Yi‐Jen , Ciombor, Kristen K. , Cohen, Stacey A. , Hussan, Hisham , Miller, Eric D. , Patel, Hitendra, Pedersen, Katrina S. , Saltz, Leonard B. , Schneider, Charles John

Journal of the National Comprehensive Cancer Network | June 11, 2024 | Volume: 22 | Issue: 2D | Pages: No page available

10.6004/jnccn.2024.0029 Get It

Colorectal cancer (CRC) is the fourth most frequently diagnosed cancer and the second leading cause of cancer death in the United States. Management of disseminated metastatic CRC involves various active drugs, either in combination or as single agents. The choice of therapy is based on consideration of the goals of therapy, the type and timing of prior therapy, the mutational profile of the tumor, and the differing toxicity profiles of the constituent drugs. This manuscript summarizes the data supporting the systemic therapy options recommended for metastatic CRC in the NCCN Guidelines for Colon Cancer.
Anal Carcinoma, Version 2.2023, NCCN Clinical Practice Guidelines in Oncology
Benson, Al B. , Al-Hawary, Mahmoud M. , Azad, Nilofer, Chen, Yi‐Jen , Cooper, Harry S. , Deming, Dustin A. , Garrido‐Laguna, Ignacio , Grem, Jean L. , Hecht, J. Randolph, Hoffe, Sarah E. , Hunt, Steven R., Johung, Kimberly L. , Joseph, Nora, Kirilcuk, Natalie, Krishnamurthi, Smitha , Maratt, Jennifer K. , Messersmith, Wells A. , Meyerhardt, Jeffrey A. , Mulcahy, Mary F. , Nurkin, Steven, Overman, Michael J. , Patel, Hitendra , Shibata, David , Skibber, John M., Sofocleous, Constantinos T. , Stotsky‐Himelfarb, Eden, Tavakkoli, Anna , Willett, Christopher G. , Algieri, Frankie, Gurski, Lisa A., Stehman, Katie, Meyerhardt, Jeffrey A , Venook, Alan P. , Ciombor, Kristen K. , Cohen, Stacey A. , Hubbard, Joleen M. , Hussan, Hisham , Jeck, William R. , Miller, Eric D. , Parikh, Aparna R. , Patel, Hitendra, Pedersen, Katrina S. , Saltz, Leonard B. , Schneider, Charles John , Williams, Grant R.

Journal of the National Comprehensive Cancer Network | June 12, 2023 | Volume: 21 | Issue: 6 | Pages: 653-677

10.6004/jnccn.2023.0030 Get It

This discussion summarizes the NCCN Clinical Practice Guidelines for managing squamous cell anal carcinoma, which represents the most common histologic form of the disease. A multidisciplinary approach including physicians from gastroenterology, medical oncology, surgical oncology, radiation oncology, and radiology is necessary. Primary treatment of perianal cancer and anal canal cancer are similar and include chemoradiation in most cases. Follow-up clinical evaluations are recommended for all patients with anal carcinoma because additional curative-intent treatment is possible. Biopsy-proven evidence of locally recurrent or persistent disease after primary treatment may require surgical treatment. Systemic therapy is generally recommended for extrapelvic metastatic disease. Recent updates to the NCCN Guidelines for Anal Carcinoma include staging classification updates based on the 9th edition of the AJCC Staging System and updates to the systemic therapy recommendations based on new data that better define optimal treatment of patients with metastatic anal carcinoma.
Esophageal and Esophagogastric Junction Cancers, Version 2.2023, NCCN Clinical Practice Guidelines in Oncology
D’Amico, Thomas A., Bentrem, David J., Cooke, David J. , Corvera, Carlos U. , Das, Prajnan , Enzinger, Peter C. , Enzler, Thomas , Farjah, Farhood , Gerdes, Hans, Grierson, Patrick , Hofstetter, Wayne L. , Ilson, David H. , Jalal, Shadia I. , Keswani, Rajesh N. , Kleinberg, Lawrence , Lacy, Jill , Licciardi, Frank, Ly, Quan P. , Matkowskyj, Kristina A. , McNamara, Michael, Miller, Aaron , Mukherjee, Sarbajit , Mulcahy, Mary F. , Poultsides, George A. , Reznik, Scott I. , Roses, Robert E. , Strong, Vivian E. , Su, Stacey, Wang, Hanlin L. , Wiesner, Georgia L. , Willett, Christopher G. , Yakoub, Danny , Yoon, Harry H. , McMillian, Nicole R., Pluchino, Lenora A. , Yoon, Harry, Ajani, Jaffer A. , Cooke, David, Gerdes, Hans, Gibson, Michael K. , Kim, Sunnie S. Y. , Klempner, Samuel J. , Miller, Aaron, Outlaw, Darryl Alan , Perry, Kyle A. , Pimiento, José M.

Journal of the National Comprehensive Cancer Network | April 4, 2023 | Volume: 21 | Issue: 4 | Pages: 393-422

10.6004/jnccn.2023.0019 Get It

Cancers originating in the esophagus or esophagogastric junction constitute a major global health problem. Esophageal cancers are histologically classified as squamous cell carcinoma (SCC) or adenocarcinoma, which differ in their etiology, pathology, tumor location, therapeutics, and prognosis. In contrast to esophageal adenocarcinoma, which usually affects the lower esophagus, esophageal SCC is more likely to localize at or higher than the tracheal bifurcation. Systemic therapy can provide palliation, improved survival, and enhanced quality of life in patients with locally advanced or metastatic disease. The implementation of biomarker testing, especially analysis of HER2 status, microsatellite instability status, and the expression of programmed death-ligand 1, has had a significant impact on clinical practice and patient care. Targeted therapies including trastuzumab, nivolumab, ipilimumab, and pembrolizumab have produced encouraging results in clinical trials for the treatment of patients with locally advanced or metastatic disease. Palliative management, which may include systemic therapy, chemoradiation, and/or best supportive care, is recommended for all patients with unresectable or metastatic cancer. Multidisciplinary team management is essential for all patients with locally advanced esophageal or esophagogastric junction cancers. This selection from the NCCN Guidelines for Esophageal and Esophagogastric Junction Cancers focuses on the management of recurrent or metastatic disease.
Rectal Cancer, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology
Benson, Al B. , Al-Hawary, Mahmoud M. , Azad, Nilofer, Chen, Yi‐Jen , Cooper, Harry S. , Deming, Dustin A. , Garrido‐Laguna, Ignacio , Grem, Jean L. , Hecht, J. Randolph, Hoffe, Sarah E. , Hunt, Steven R., Johung, Kimberly L. , Kirilcuk, Natalie, Krishnamurthi, Smitha , Maratt, Jennifer K. , Messersmith, Wells A. , Meyerhardt, Jeffrey A. , Mulcahy, Mary F. , Nurkin, Steven, Overman, Michael J. , Parikh, Aparna, Patel, Hitendra , Shibata, David , Skibber, John M., Sofocleous, Constantinos T. , Stotsky‐Himelfarb, Eden, Tavakkoli, Anna , Willett, Christopher G. , Gregory, Kristina M., Gurski, Lisa A., Meyerhardt, Jeffrey A , Venook, Alan P. , Ciombor, Kristen K. , Cohen, Stacey A. , Gunn, Andrew, Hubbard, Joleen M. , Jeck, William R. , Miller, Eric D. , Patel, Hitendra, Pedersen, Katrina S. , Saltz, Leonard B. , Schneider, Charles John

Journal of the National Comprehensive Cancer Network | October 14, 2022 | Volume: 20 | Issue: 10 | Pages: 1139-1167

10.6004/jnccn.2022.0051 Get It

This selection from the NCCN Guidelines for Rectal Cancer focuses on management of malignant polyps and resectable nonmetastatic rectal cancer because important updates have been made to these guidelines. These recent updates include redrawing the algorithms for stage II and III disease to reflect new data supporting the increasingly prominent role of total neoadjuvant therapy, expanded recommendations for short-course radiation therapy techniques, and new recommendations for a “watch-and-wait” nonoperative management technique for patients with cancer that shows a complete response to neoadjuvant therapy. The complete version of the NCCN Guidelines for Rectal Cancer, available online at NCCN.org , covers additional topics including risk assessment, pathology and staging, management of metastatic disease, posttreatment surveillance, treatment of recurrent disease, and survivorship.
Gastric Cancer, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology
D’Amico, Thomas A., Bentrem, David J. , Cooke, David T. , Corvera, Carlos U. , Das, Prajnan , Enzinger, Peter C. , Enzler, Thomas , Fanta, Paul T. , Farjah, Farhood , Gerdes, Hans, Hochwald, Steven N. , Hofstetter, Wayne L. , Ilson, David H. , Keswani, Rajesh N. , Kleinberg, Lawrence , Lacy, Jill , Ly, Quan P. , Matkowskyj, Kristina A. , McNamara, Michael J. , Mulcahy, Mary F. , Park, Haeseong , Poultsides, George A. , Reznik, Scott I. , Roses, Robert E. , Strong, Vivian E. , Su, Stacey, Wang, Hanlin L. , Wiesner, Georgia L. , Willett, Christopher G. , Yakoub, Danny , Yoon, Harry H. , McMillian, Nicole R., Pluchino, Lenora A. , Yoon, Harry, Ajani, Jaffer A. , Bentrem, David J. , Chao, Joseph , Gibson, Michael K. , Kim, Sunnie S. Y. , Klempner, Samuel J. , Outlaw, Darryl Alan , Perry, Kyle A. , Pimiento, José M.

Journal of the National Comprehensive Cancer Network | February 7, 2022 | Volume: 20 | Issue: 2 | Pages: 167-192

10.6004/jnccn.2022.0008 Get It

Gastric cancer is the third leading cause of cancer-related deaths worldwide. Over 95% of gastric cancers are adenocarcinomas, which are typically classified based on anatomic location and histologic type. Gastric cancer generally carries a poor prognosis because it is often diagnosed at an advanced stage. Systemic therapy can provide palliation, improved survival, and enhanced quality of life in patients with locally advanced or metastatic disease. The implementation of biomarker testing, especially analysis of HER2 status, microsatellite instability (MSI) status, and the expression of programmed death-ligand 1 (PD-L1), has had a significant impact on clinical practice and patient care. Targeted therapies including trastuzumab, nivolumab, and pembrolizumab have produced encouraging results in clinical trials for the treatment of patients with locally advanced or metastatic disease. Palliative management, which may include systemic therapy, chemoradiation, and/or best supportive care, is recommended for all patients with unresectable or metastatic cancer. Multidisciplinary team management is essential for all patients with localized gastric cancer. This selection from the NCCN Guidelines for Gastric Cancer focuses on the management of unresectable locally advanced, recurrent, or metastatic disease.
Colon Cancer, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology
Benson, Al B. , Al-Hawary, Mahmoud M. , Arain, Mustafa A., Chen, Yi‐Jen , Ciombor, Kristen K. , Cooper, Harry S. , Deming, Dustin A. , Farkas, Linda M., Garrido‐Laguna, Ignacio , Grem, Jean L. , Hecht, J. Randolph, Hoffe, Sarah E. , Hunt, Steven R., Johung, Kimberly L. , Kirilcuk, Natalie, Krishnamurthi, Smitha , Messersmith, Wells A. , Meyerhardt, Jeffrey A. , Mulcahy, Mary F. , Nurkin, Steven, Overman, Michael J. , Patel, Hitendra , Pedersen, Katrina S. , Shibata, David , Skibber, John M., Sofocleous, Constantinos T. , Stotsky‐Himelfarb, Eden, Willett, Christopher G. , Gregory, Kristina M., Gurski, Lisa A., Hubbard, Joleen, Meyerhardt, Jeffrey A , Pedersen, Katrina , Venook, Alan P. , Cohen, Stacey A. , Gunn, Andrew, Hubbard, Joleen M. , Miller, Eric D. , Parikh, Aparna R. , Patel, Hitendra, Saltz, Leonard B. , Schneider, Charles John , Stoffel, Elena M.

Journal of the National Comprehensive Cancer Network | March 5, 2021 | Volume: 19 | Issue: 3 | Pages: 329-359

10.6004/jnccn.2021.0012 Get It

This selection from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Colon Cancer focuses on systemic therapy options for the treatment of metastatic colorectal cancer (mCRC), because important updates have recently been made to this section. These updates include recommendations for first-line use of checkpoint inhibitors for mCRC, that is deficient mismatch repair/microsatellite instability-high, recommendations related to the use of biosimilars, and expanded recommendations for biomarker testing. The systemic therapy recommendations now include targeted therapy options for patients with mCRC that is HER2-amplified, or BRAF V600E mutation–positive. Treatment and management of nonmetastatic or resectable/ablatable metastatic disease are discussed in the complete version of the NCCN Guidelines for Colon Cancer available at NCCN.org . Additional topics covered in the complete version include risk assessment, staging, pathology, posttreatment surveillance, and survivorship.
Prognostic Factors in Colorectal Cancer
Fielding, L P, Burgart, Lawrence J., Conley, Barbara A. , Cooper, Harry S. , Hammond, M. Elizabeth, Henson, Donald E., Hutter, R. V. P., Nagle, Raymond B., Nielsen, Mary L., Welton, Mark L., Willett, Christopher G. , Compton, Carolyn C. , Hamilton, Stanley R. , Sargent, Daniel J. , Taylor, Clive R.

Archives of Pathology & Laboratory Medicine | January 28, 2021 | Volume: 124 | Issue: 7 | Pages: 979-994

10.5858/2000-124-0979-pficc Get It

Abstract Background. —Under the auspices of the College of American Pathologists, the current state of knowledge regarding pathologic prognostic factors (factors linked to outcome) and predictive factors (factors predicting response to therapy) in colorectal carcinoma was evaluated. A multidisciplinary group of clinical (including the disciplines of medical oncology, surgical oncology, and radiation oncology), pathologic, and statistical experts in colorectal cancer reviewed all relevant medical literature and stratified the reported prognostic factors into categories that reflected the strength of the published evidence demonstrating their prognostic value. Accordingly, the following categories of prognostic factors were defined. Category I includes factors definitively proven to be of prognostic import based on evidence from multiple statistically robust published trials and generally used in patient management. Category IIA includes factors extensively studied biologically and/or clinically and repeatedly shown to have prognostic value for outcome and/or predictive value for therapy that is of sufficient import to be included in the pathology report but that remains to be validated in statistically robust studies. Category IIB includes factors shown to be promising in multiple studies but lacking sufficient data for inclusion in category I or IIA. Category III includes factors not yet sufficiently studied to determine their prognostic value. Category IV includes factors well studied and shown to have no prognostic significance. Materials and Methods. —The medical literature was critically reviewed, and the analysis revealed specific points of variability in approach that prevented direct comparisons among published studies and compromised the quality of the collective data. Categories of variability recognized included the following: (1) methods of analysis, (2) interpretation of findings, (3) reporting of data, and (4) statistical evaluation. Additional points of variability within these categories were defined from the collective experience of the group. Reasons for the assignment of an individual prognostic factor to category I, II, III, or IV (categories defined by the level of scientific validation) were outlined with reference to the specific types of variability associated with the supportive data. For each factor and category of variability related to that factor, detailed recommendations for improvement were made. The recommendations were based on the following aims: (1) to increase the uniformity and completeness of pathologic evaluation of tumor specimens, (2) to enhance the quality of the data needed for definitive evaluation of the prognostic value of individual prognostic factors, and (3) ultimately, to improve patient care. Results and Conclusions. —Factors that were determined to merit inclusion in category I were as follows: the local extent of tumor assessed pathologically (the pT category of the TNM staging system of the American Joint Committee on Cancer and the Union Internationale Contre le Cancer [AJCC/UICC]); regional lymph node metastasis (the pN category of the TNM staging system); blood or lymphatic vessel invasion; residual tumor following surgery with curative intent (the R classification of the AJCC/UICC staging system), especially as it relates to positive surgical margins; and preoperative elevation of carcinoembryonic antigen elevation (a factor established by laboratory medicine methods rather than anatomic pathology). Factors in category IIA included the following: tumor grade, radial margin status (for resection specimens with nonperitonealized surfaces), and residual tumor in the resection specimen following neoadjuvant therapy (the ypTNM category of the TNM staging system of the AJCC/UICC). Factors in category IIB included the following: histologic type, histologic features associated with microsatellite instability (MSI) (ie, host lymphoid response to tumor and medullary or mucinous histologic type), high degree of MSI (MSI-H), loss of heterozygosity at 18q ( DCC gene allelic loss), and tumor border configuration (infiltrating vs pushing border). Factors grouped in category III included the following: DNA content, all other molecular markers except loss of heterozygosity 18q/DCC and MSI-H, perineural invasion, microvessel density, tumor cell–associated proteins or carbohydrates, peritumoral fibrosis, peritumoral inflammatory response, focal neuroendocrine differentiation, nuclear organizing regions, and proliferation indices. Category IV factors included tumor size and gross tumor configuration. This report records findings and recommendations of the consensus conference group, organized according to structural guidelines defined herein.
NCCN Guidelines Insights: Rectal Cancer, Version 6.2020
Benson, Al B. , Al-Hawary, Mahmoud M. , Arain, Mustafa A., Chen, Yi‐Jen , Ciombor, Kristen K. , Cooper, Harry S. , Deming, Dustin A. , Garrido‐Laguna, Ignacio , Grem, Jean L. , Hoffe, Sarah E. , Hunt, Steven R., Kirilcuk, Natalie, Krishnamurthi, Smitha , Messersmith, Wells A. , Meyerhardt, Jeffrey A. , Miller, Eric D. , Mulcahy, Mary F. , Nurkin, Steven, Overman, Michael J. , Patel, Hitendra , Pedersen, Katrina S. , Shibata, David , Skibber, John M., Sofocleous, Constantinos T. , Stotsky‐Himelfarb, Eden, Willett, Christopher G. , Johnson-Chilla, Alyse, Gurski, Lisa A., Hubbard, Joleen, Miller, Eric D. , Meyerhardt, Jeffrey A , Pedersen, Katrina , Venook, Alan P. , Cohen, Stacey A. , Gunn, Andrew, Hubbard, Joleen M. , Parikh, Aparna R. , Patel, Hitendra, Saltz, Leonard B. , Schneider, Charles John , Stoffel, Elena M.

Journal of the National Comprehensive Cancer Network | July 7, 2020 | Volume: 18 | Issue: 7 | Pages: 806-815

10.6004/jnccn.2020.0032 Get It

The NCCN Guidelines for Rectal Cancer provide recommendations for the diagnosis, evaluation, treatment, and follow-up of patients with rectal cancer. These NCCN Guidelines Insights summarize the panel discussion behind recent important updates to the guidelines. These updates include clarifying the definition of rectum and differentiating the rectum from the sigmoid colon; the total neoadjuvant therapy approach for localized rectal cancer; and biomarker-targeted therapy for metastatic colorectal cancer, with a focus on new treatment options for patients with BRAF V600E– or HER2 amplification–positive disease.